package jdbc;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class JDBCDemo6 {
    public static void main(String[] args) {
        try (Connection connection =DBUtil.getconnection()){
            Statement statement=connection.createStatement();
            String sql="select count(*) count " +
                    "from class c " +
                    "join student s on c.id=s.class_id " +
                    "where c.name='1年级1班' ";
            ResultSet rs=statement.executeQuery(sql);
            while (rs.next()){
                int count =rs.getInt("count");
                System.out.println("人数:"+count);
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}
